Post automatically merged, why?

For the past few days, some posts have been automatically merged. In my opinion, this is making things less clear.
What do you think?
My today post was merged to yesterday post too. I think it's not so good. Posts merged function will be good, if merged last 20min. comments together. If merged with previous day, then it's not showing as new post and users can't see it as new.
 
I see what you mean and I have changed it so that it merges posts within 5 minutes and after that it will start a new post.

Thanks for letting me know.